#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
bool isUnique(char* str)
{
    // write code here
    bool ture = 1;
    if (*(str + 1) == '\0')
        return 1;

    char* Front = str, * Back = str + 1;
    while (*Front)
    {
        while (*Back)
        {
            if (*Front == *Back)
            {
                return 0;
            }
            Back++;
        }
        Front++;
        if (*Front)
            Back = Front + 1;
    }
    return 1;
}
int main()
{
    char arr[] = "abcdefghi";
    printf("%d\n",isUnique(arr));
	return 0;
}